Opacity and Pigments
To talk about Colors and Color Theory, we should introduce some basics about Pigments.
When light waves strike a painted surface, they are affected by the pigments’ degree of transparency, translucency or opaqueness.
- Each pigment has its own specific attributes that affect how it interacts with light waves. For example, the high opacity of Titanium White or Yellow Ochre is largely responsible for its ability to hide anything beneath it – even dark colors.
- When the light waves hit a highly opaque layer of color, the particles block the light penetration and the waves bounce off without interacting with the underlying colors.
- Translucent colors, on the other hand, absorb some light and reflect some back, therefore they are influenced by the surface beneath the paint (think about « glazing » techniques).
Pigments are organized into two main categories based on their origins: « Organic » or « Modern » pigments are synthetic and very translucent. In other words, light waves are able to penetrate the translucent paint film and reflect the surface below back to the eye. Because of their translucency, organic pigments are perfect for staining, glazing and working in layers. When working in this manner, each layer of color is influenced by the color beneath it, resulting in rich, complex and saturated hues.
Modern pigments have names that allude to their chemical origins, like quinacridone, phthalo, hansa, dioxazine, and anthraquinone. They are generally characterized by:
- High translucency (very transparent)
- High chroma (very vibrant)
- High tinting (strongly change the colors they are mixed with)
Another classification of pigments is called « Inorganic » or « Mineral » pigments.These are opaque in their basic makeup, so light waves cannot penetrate below the surface of the paint layer to reflect the color of the substrate back to the eye. Because the microscopic pigment particles are dense, light waves simply bounce off the top layer. These opaque mineral colors are less intense in hue (synonym: color, tone, shade, tint, tinge, cast, tincture) than modern colors and are not suitable for glazing.
Mineral pigments have earthy-sounding names like sienna, ochre, cadmium, cobalt and ultramarine. They are generally charaterized by:
- High opacity (very opaque)
- Low chroma (less vibrant)
- Low tinting strength (do not strongly change the colors they are mixed with)
When using acrylics, use mineral colors if you want to completely cover the surface or color beneath, and use modern colors if you want to glaze and allow the surface or color beneath to show through. You are not limited to choosing one or the other, you can mix mineral and modern paints together to achieve greater color subtleties and nuances.
Beware that mixing a translucent color with titanium white (which has high refractive indices = high opacity) will not bring a paler version of the color.
- Apply a thin glaze of ultramarine on a white surface, and a brilliant blue will result. Similarly, apply a thin glaze of permanent rose on a white surface and a brilliant pink will be the outcome.
- Mix ultramarine with white, and an opaque, rather grayish, flat blue will come back. Mix permanent rose with white, and a candy-floss pink will be the consequence.
- Mix a Cadmium Red Medium and Cobalt Blue (inorganics) to create violet. Now use Quinacridone Red and Phthalo Blue (organics) to make another violet.
- Translucent pigments are ideal for glazing techniques, but careful mixing is required if an opaque paint layer is needed.
Let’s take an example to illustrate the theory explained above. Take a look at the different versions of the Matisse painting below (yes it is not a miniature, but this will do the trick!). One is painted with a limited palette of organics (left painting) and the other inorganics (right painting).
One is not a better palette than the other, but by understanding the “rules” of pigment mixing, you have solved many color mixing dilemmas and maybe even hours of mixing muddy color.
Light and Shadows
When painting highlights and shadows on a miniature, you are not only describing the silhouette but also communicating about the environmental influences. Beginning painters often add white to lighten and black to darken the color, but there are much more authentic ways to simulate the colors of an object or figure in light. Below three common approaches:
- Add a touch of yellow or orange to all parts of a subject/figure struck by warm light, along with blue or purple to all areas in shadow.
- Create the shadow color by adding the local color’s complement. For example if your miniature has a basecoat of red, add deep green to the base color (but careful this results in dull shadow colors you will have to enhance).
- Use hues that are adjacent to the base-color on the color wheel. either lighter, warmer or darker and cooler.
Locating colors outside of the color wheel
It is known that true opposite colors on the color wheel complement each other and work visually together very well ! How can we determine which colors are true opposites and thus perfectly compatible ?
This is where you will be looking for the “neutralization of colors”; when you mix 2 complementary colors together and reach a point where they gray each other out and neither color can be seen.
When the middle wash is looked at closely, neither the yellow nor the violet can be seen. This same process of experimenting can be done with every color to find its true complement. By the way, do not confuse the term graying with the color gray. This term means strictly that in the mixed neutral, neither complementary color can be seen. It is simply a neutral color, not necessarily gray. When two colors do gray each other out, it means two very important things:
- These are true complementary colors that will create optimum optical color balance if used together well.
- These two colors will create beautiful semi-neutrals and thus an appealing visual quality when mixed correctly.
Neutrals and Semi-Neutrals
In case you are wondering about the difference between neutrals and semi-neutrals, semi-neutrals are the intermediate steps as mixtures of ure colors appreach a neutral. In neutrals, neither complement is visible; a semi-neutral contains more of one pure color than the other.
Not only do the primary, secondary, and tertiary colors create pleasing semi-neutrals, but they also create all the remaining pure colors (those located on the outside of the color wheel, between the primaries, secondaries and tertiaries).